<template>
  <div id="root">
    <div class="todo-container">
      <div class="todo-wrap">
        <MyHeader @addTodo="addTodo"/>
        <MyList :todos="todos"/>
        <MyFooter :todos="todos" @checkAllTodo="checkAllTodo" @clearAllTodo="clearAllTodo"/>
      </div>
    </div>
  </div>

</template>
<script>
  import pubsub from 'pubsub-js'

  import MyHeader from './components/MyHeader.vue'
  import MyFooter from './components/MyFooter.vue'
  import MyItem from './components/MyItem.vue'
  import MyList from './components/MyList.vue'


	export default {
		name:'App',
    components:{MyHeader,MyFooter,MyItem,MyList},
    data(){
      return{
       //由于todos是MyHeader组件 和MyFooter组件都在使用，所以放在app里
        todos:JSON.parse(localStorage.getItem('todos'))  || []

      }
    },
    methods:{
      addTodo(todoObj){
       /* console.log('我是App组件，我收到了数据',x) */
        this.todos.unshift(todoObj)
      },
      //更新一个todo
      updateTodo(id,title){
        this.todos.forEach((todo)=>{
          if(todo.id === id) todo.title = title
        })
      },
      /* 勾选 or 取消勾选todo */
      checkTodo(id){
        this.todos.forEach((todo)=>{
          if(todo.id === id) todo.done = !todo.done
        })
      },
      /* 删除一个todo */
      deleteTodo(_,id){
        this.todos = this.todos.filter((todo) =>{
          return todo.id !== id
        })
      },
      //全 选or取消全选
      checkAllTodo(done){
        this.todos.forEach((todo)=>{
          todo.done = done
        })
      },
      /* 清空所有 */
      clearAllTodo(){
        this.todos = this.todos.filter((todo)=>{
          return !todo.done
        })


      }
    },
    watch: {
      todos:{
        deep:true,
        handler(value){
          localStorage.setItem('todos',JSON.stringify(value))
        }
      }
    },
    mounted(){
      this.$bus.$on('checkTodo',this.checkTodo)
      // this.$bus.$on('deleteTodo',this.deleteTodo)
      this.$bus.$on('updateTodo',this.updateTodo)
     this.pubId = pubsub.subscribe('deleteTodo',this.deleteTodo)
    },
    beforeDestroy() {
      this.$bus.$off('checkTodo')
      this.$bus.$off('updateTodo')
      // this.$bus.$off('deleteTodo')
      pubsub.unsubscribe('this.pubId')
    }
  }
</script>


<style>
  /*base*/
  body {
    background: #fff;
  }

  .btn {
    display: inline-block;
    padding: 4px 12px;
    margin-bottom: 0;
    font-size: 14px;
    line-height: 20px;
    text-align: center;
    vertical-align: middle;
    cursor: pointer;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
    border-radius: 4px;
  }

  .btn-danger {
    color: #fff;
    background-color: #da4f49;
    border: 1px solid black;
  }
  .btn-edit {
    color: #fff;
    background-color: deepskyblue;
    border: 1px solid black;
    margin-right:5px;
  }

  .btn-danger:hover {
    color: #fff;
    background-color: #bd362f;
  }

  .btn:focus {
    outline: none;
  }

  .todo-container {
    width: 600px;
    margin: 0 auto;
  }
  .todo-container .todo-wrap {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
  }



</style>